US Registration for small vessels

[marty007]

Hello,

I'm Canadian based, so please excuse my ignorance.

For small pressure vessels in Canada, we have a separate registration requirements (H-fitting). I'm trying to understand if there is an equivalent system for vessels in the United States (specifically in Tennessee).

As an example, we have a small vessel (less than 5 ft3) being shipped to and installed in Tennessee. Per National Board document NB-370, it appears that there is an exemption for vessels under 5 ft3. Does this mean no registration of any kind is required? Can we just ship the vessel to site and they can bolt it up?

Thank you,
Marty

 

[JStephen]

In the US, there are boiler and pressure vessel laws, but they are state legislation, not national. So you need to look up the laws or rules in Tennessee specifically. They are likely online. It may be a "boiler and pressure vessel" law, not just a PV law.

Quite likely, a vessel that is exempt per the exemptions in the ASME code would be exempt from state regulations as well, but you'd need to confirm that via state law.

 

[GenB]

What is the Code of construction? That will determine the State acceptance then you look at the rules to see if exempted. I would still register it with the National Board it only cost you a couple Dollars... USD

 

[GenB]

Pls also tell us pressure rating MAWP

 

[marty007]

Per National Board document NB-370 I don't think this information is required to answer the question, but here it is anyways:
Code: ASME VIII-1
MAWP: 90psi @ 331°F

The specific state regulation: Tennessee state regulation.
Paragraph 68-122-105(a)(5) states: (a)This part shall not apply to the following boilers: (5) Unfired pressure vessels having a volume of five (5) cubic feet or less.

So, my question again, is any registration required for a small pressure vessel less than 5 ft3 in Tennessee? Could I ship a vessel there with an MAWP of 10,000psi but a volume of 4.9 ft3 with no registration?

(I'm just asking because it seems odd coming from a Canadian h-fitting background)

Thanks,
Marty

 

[JStephen]

That would be my understanding.

 

[GenB]

Finally you are given PCs of info. And playing it. Yes you will need propped ASME designator mark and also NB registration. All The Union States require it at that pressure.

 

[moltenmetal]

Whether the device needs to be National Board registered is totally separate from whether or not it needs a U or UM stamp. There are NB states and there are states where there is no NB registration requirement. ASME VIII determines what is within the scope of ASME VIII, and similar to Canada's provinces, individual states determine whether or not ASME VIII is a de-facto regulation or whether it needs to be supplemented with additional requirements.

The Category H fitting designation under CSAB51 is very poorly understood in my opinion. Lots of stuff gets separately registered as a Category H fitting when it is really nothing more than a wide spot in the pressure piping system which itself is registered and given a CRN. Category H is intended for articles which will be manufactured repeatedly for sale and hence need independent CRNs, not for one-off small "vessels" falling below the scope of ASME VIII. B51 is poorly written so the misunderstanding is widespread.

 

[XL83NL]

marty007, if you review NB-370, Tennessee state, it is written that

OBJECTS SUBJECT TO RULES FOR CONSTRUCTION AND STAMPING
All boilers and pressure vessels, except the following:
...
..
5. Unfired pressure vessels:
a. Having a volume of 5 cubic feet or less;
b. Designed for a working pressure of 15 psi or less

Maybe that answers your question?

 

[metalonis]

Hmmm ... The exemption in Tennessee reads

Unfired pressure vessels:
a. Having a volume of 5 cubic feet or less;
b. Designed for a working pressure of 15 psi or less.

I always considered both conditions need to be met but now I'm not so sure.

Also it's not true that all states require ASME and NB registration. Some states don't even have pressure vessel laws.

 

[SnTMan]

I have in the past found it useful to talk to the jurisdiction.

Regards,

Mike

 

[marty007]

XL83NL, metalonis,
NB-370 is trying to summarize from the state laws. If you leaf through the state law however, those two exemptions are listed under separate lines as independent exemptions.

SnTMan,
I was hoping this would garner a quick response from the collective knowledge. I guess not, time to wade through the jurisdictional telephone soup.

Cheers,
Marty

 

[SnTMan]

marty007, yeah, whatever you can glean here and elsewhere, the jurisdiction has the Official Say.

Good luck,

Mike

 

[SnTMan]

At least it ain't Alberta

 

[Duwe6]

. . . and the Sect VIII Div-1 exemption is <5 cu-ft and <300 psi. Willing to bet that that was the intent of the Tennessee law.